From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Design, manufacturing, and fitting challenges of rivetless bonnets.
| Identifier | WestWitteringFiles\V\March1931-September1931\ Scan382 | |
| Date | 25th August 1931 | |
| HS.{Lord Ernest Hives - Chair} FROM DA{Bernard Day - Chassis Design}/EV.{Ivan Evernden - coachwork} C. to SG.{Arthur F. Sidgreaves - MD} WOR{Arthur Wormald - General Works Manager} C. to DY.{F R Danby} E.{Mr Elliott - Chief Engineer} ORIGINAL. DA{Bernard Day - Chassis Design}/EV{Ivan Evernden - coachwork}2/M2/.8.31. x385. RIVETLESS BONNETS. We thank you for your HS{Lord Ernest Hives - Chair}/LID{A. J. Lidsey}2/AD25831., and note your remarks. We are very anxious to have a model to shew SG.{Arthur F. Sidgreaves - MD}, especially as our coachbuilders will have such a bonnet on one of our cars at the Paris Salon. We have no instructions to put the shutter pivot centre in the middle of the flap, and do not see why we should make the shutter any different from that approved and standardised on P. 2. N. 2.series. We do not know anything about PN{Mr Northey}'s request for the symmetry of the shutters, and do not understand what is meant. We have given you a design for the shutter position in the P.2.bonnet. We think it is hopeless to again try countersunk rivets as we know they will crack the paint. We believe that the 4 rivets per shutter will have to be snap headed. We shall have made a big move to have reduced the rivets in the bonnet to 16 in all. We note that you are producing N. sch. 3244. It is felt that for too long have we theorised on this subject; we have said before that the design dept. cannot do any more until some tests have been made. We therefore ask you to also make at least a portion of a side and top hinge to N. sch. 3304. and test it, for although theories may prove it unlikely to be good we have Armstrong using it, and Hooper's have adopted a modification of it. We fail to believe that in these days bonnets are "made to measure". If the panels are shaped and fitted to each individual chassis we are indeed surprised. We understood that the only fitting done was the filing at the ends to get correct clearances between the bonnet and the radiator or dash. Now that the bonnet passes over the dash we anticipated much of this fitting would disappear. (ReadOY's remarks on this matter.) We would be glad to have an explanation from the Production people of the difficulties experienced in making and fitting bonnets to RR. cars, with a view to studying the design to remove them as far as possible. We believe bonnets ought to be made up to a jig. DA{Bernard Day - Chassis Design}/EV.{Ivan Evernden - coachwork} | ||